Having two copies of the mutated genes cause sickle cell anemia, but having just one copy does not, and can actually protect against malaria - an example of how mutations are sometimes beneficial.
The majority of mutations have neither negative nor positive effects on the organism in which they occur. These mutations are called neutral mutations. Examples include silent point mutations. They are neutral because they do not change the amino acids in the proteins they encode.
Hope this helped :)
Answer: The cell membrane is selectively permeable.
Explanation: going thru last year notes
The cell membranes begin to come apart when there is insufficient water around the cells. The cytoplasm of the cells becomes more concentrated, which slowly poisons the cells. The cell walls become brittle as they dry out, and some of them collapse. The central vacuoles in the cells lose water and can no longer help support the cells.
The central vacuoles in the cells lose water and can no longer help support the cells
